1. Technical Field
Embodiments of the present invention generally relate to a semiconductor device and an operating method thereof, more particularly to a semiconductor device capable of monitoring events and an operating method thereof, and more particularly to a semiconductor device capable of monitoring word line access of a semiconductor memory device and operating method thereof.
2. Related Art
A semiconductor memory device monitoring events during a predetermined period may comprise a register storing event information. For example, if a semiconductor device monitors word line access of a semiconductor memory device, the register may store event information comprising an address of a word line and number of accesses to the word line.
FIG. 1 is a block diagram illustrating a data structure of a register used to monitor a word line access for the 2 Gb Dynamic Random Access Memory (DRAM).
The count field stores number of accesses to a corresponding word line and the valid field stores a flag indicating whether information of the corresponding row is valid or not.
The register illustrated in FIG. 1 requires memory space as large as 4.5 Mb. The size of this memory space corresponds to 25% of that of a commercial memory controller, which is too large.
Moreover as the level of integration of semiconductor memory device increases, coupling effect between word lines gets worse. For example, as a word line toggles between active and inactive states, a memory cell in a word line neighboring the toggling word line comes to lose its data. To overcome this word line disturbance effect, a semiconductor device which can efficiently monitor word line access becomes necessary.